Pre-Employment Mantoux Tests for Health Care Workers

The Mantoux skin test checks individuals for tuberculosis infections. Healthcare workers must periodically receive these tests because tuberculosis, or TB, is easily transmitted and can be particularly dangerous for anyone with a compromised immune system. Prior to employment in the medical field employment, you will need a TB test. You may also need additional tests during your career, and a couple of different tests could be given.

Standard Mantoux Skin Test

The basic Mantoux skin test normally involves two parts. First, you receive a dose of tuberculin protein. The protein is injected under the skin of your forearm using a syringe. Second, you must return within the next 2 to 3 days to have the results examined. If the area of the injection shows bumps 10 to 15 millimeters or more in diameter, you test positive for the presence of the bacteria that causes TB.

Two-Step Mantoux Testing

For health care workers, the two-step Mantoux skin test is more frequently used than the basic method of TB testing. Because some people may not initially test positive even if they are infected with the bacteria, the test is given twice. The first test makes the bacteria more active so the second test can provide an accurate reading. The process for each separate Mantoux skin test in this approach is the same, but the entire process is repeated within 1 to 3 weeks of the initial skin test unless the first test shows positive results.

Chest Radiography

When your skin test comes back positive and/or you are showing clinical signs of tuberculosis, you may need to have a chest X-ray, so the presence of the disease can be verified. Even if the initial X-ray does not show any signs of TB infection, you will have another X-ray done in six months.

QuantiFERON-TB Gold

Although the Mantoux skin test has been used for many years successfully and safely, an alternative testing method has been approved by the FDA for use in the United States. Known as QuantiFERON-TB Gold, this test requires blood to be drawn from the patient, then transported for testing within 12 hours to the laboratory. In the lab, the blood is mixed with proteins that normally react to the presence of the bacteria that causes tuberculosis. The test can provide results in 24 hours and does not require a return visit from the person. However, the test cannot be given to people with suppressed immune systems, under 17, or who are pregnant.

Job Implications

The Francis J. Curry National Tuberculosis Center provides a guide for Mantoux testing of workers in health facilities. Individual facilities may customize their testing requirements according to state and local law and the needs of the particular facility. For example, health care workers with direct patient contact, such as physicians and nurses, would normally be tested, but testing of support staff, such as clerks and cleaning workers, might vary. A worker's whose Mantoux and follow-up tests show a contagious, active infection receives treatment. Once the disease is no longer infectious, she needs permission from a medical professional to start a job or return to work.